What can the 'Map' be used for?

So after resetting my run and updating to 1.4.5.1.c (current is .f), I found a new feature in my village tab. It consisted of a map, with fields, available to be explored.
I checked the wiki, and there doesn't seem to be anything on it yet.

Exploring a field would add a small percentage to the three values shown in the screenshot below ('Explored', 'Exploration bonus', and most notably 'Price reduction'), in exchange for a small, but long-lasting decrease in catpower production. Exploring a field would also make re-exploring it more expensive, and would sometimes enlarge the map.

Here is a screenshot of the map (from my save):

The price of exploring increases exponentially the more the field is explored, and the further away it is. So after time, the total number of explored fields will slowly level out.

Given a reasonably high number of explorations, let's say, 500, one would still only have a ~0.12% price reduction – if there aren't diminishing returns. Which is quite low, given the millions of cp and many hours it would take to get there.

So the question is, does the map feature give any other benefit then a slight price reduction (which would only help buy a few buildings late-game)? And as a side question, what triggers the map to appear?